(a) Field of the Invention
The present invention relates to a air supply system of an automobile and methods employing thereof that are capable of preventing a vehicle from suddenly accelerating regardless of a driver's intention so as to secure a vehicle's stability and driver's safety.
(b) Description of the Related Art
Generally, an automatic torque converter comprises a torque converter, a gear train connected the torque converter for achieving a wide range of speeds and loads, and a hydraulic control system for selecting a necessary gear ratio by applying or releasing hydraulic pressure to or from desired friction elements.
Thus, in a vehicle equipped with an automatic transmission, gear shifting is performed by an electronic control unit (ECU), which sends electric control signals to a plurality of solenoid valves for controlling hydraulic flows, a medium for operating friction elements.
Recently, traffic accidents caused by sudden acceleration without relation to the driver's intention have been reported and one reason of these sudden accelerations is thought to be malfunctions of the solenoid valves caused by electromagnetic waves.
However, in a normal running state of the vehicle, such an uncontrolled sudden acceleration can not theoretically occur because the hydraulic flow control is ultimately performed by the driver's shift lever manipulation. Furthermore, even when there is a malfunction, the gear ratio is locked in third gear.
Other possible causes of uncontrolled accelerations of these vehicles are though to be as follows:
first, a speed range shift due to select lever manipulation while the accelerator is depressed; PA1 second, a speed range shift when the idle revolutions per minute (rpm) of the engine is above normal due to an insufficient warm up of the engine; PA1 third, a malfunction of the ECU caused by the driver's habitual tapping on the acceleration pedal, which temporarily increases the engine rpm; PA1 and finally, a speed range shift that occurs if the vehicle is started without depressing the brake pedal, a situation in which the engine rpm increases temporally to compensate for the load generated during a speed range shift.
Recently, various technologies for preventing the vehicle's uncontrolled acceleration have been proposed. Most of the uncontrolled acceleration preventing technologies adapt a method for the analysis of the vehicle speed, the gear ratio of the transmission, and the engine rpm so as to adjust the engine performance if any unbalance is detected.
However, electrical analysis technologies for adjusting engine rpm use electrical circuit devices for detecting a failure. Hence, such devices are also susceptible to the effects of electromagnetic waves.